Data commit

Task/Arithmetic-Complex/Elixir/arithmetic-complex.elixir

@@ -0,0 +1,85 @@
+defmodule Complex do
+  import Kernel, except: [abs: 1, div: 2]
+
+  defstruct real: 0, imag: 0
+
+  def new(real, imag) do
+    %__MODULE__{real: real, imag: imag}
+  end
+
+  def add(a, b) do
+    {a, b} = convert(a, b)
+    new(a.real + b.real, a.imag + b.imag)
+  end
+
+  def sub(a, b) do
+    {a, b} = convert(a, b)
+    new(a.real - b.real, a.imag - b.imag)
+  end
+
+  def mul(a, b) do
+    {a, b} = convert(a, b)
+    new(a.real*b.real - a.imag*b.imag, a.imag*b.real + a.real*b.imag)
+  end
+
+  def div(a, b) do
+    {a, b} = convert(a, b)
+    divisor = abs2(b)
+    new((a.real*b.real + a.imag*b.imag) / divisor,
+        (a.imag*b.real - a.real*b.imag) / divisor)
+  end
+
+  def neg(a) do
+    a = convert(a)
+    new(-a.real, -a.imag)
+  end
+
+  def inv(a) do
+    a = convert(a)
+    divisor = abs2(a)
+    new(a.real / divisor, -a.imag / divisor)
+  end
+
+  def conj(a) do
+    a = convert(a)
+    new(a.real, -a.imag)
+  end
+
+  def abs(a) do
+    :math.sqrt(abs2(a))
+  end
+
+  defp abs2(a) do
+    a = convert(a)
+    a.real*a.real + a.imag*a.imag
+  end
+
+  defp convert(a) when is_number(a), do: new(a, 0)
+  defp convert(%__MODULE__{} = a), do: a
+
+  defp convert(a, b), do: {convert(a), convert(b)}
+
+  def task do
+    a = new(1, 3)
+    b = new(5, 2)
+    IO.puts "a = #{a}"
+    IO.puts "b = #{b}"
+    IO.puts "add(a,b): #{add(a, b)}"
+    IO.puts "sub(a,b): #{sub(a, b)}"
+    IO.puts "mul(a,b): #{mul(a, b)}"
+    IO.puts "div(a,b): #{div(a, b)}"
+    IO.puts "div(b,a): #{div(b, a)}"
+    IO.puts "neg(a)  : #{neg(a)}"
+    IO.puts "inv(a)  : #{inv(a)}"
+    IO.puts "conj(a) : #{conj(a)}"
+  end
+end
+
+defimpl String.Chars, for: Complex do
+  def to_string(%Complex{real: real, imag: imag}) do
+    if imag >= 0, do: "#{real}+#{imag}j",
+                else: "#{real}#{imag}j"
+  end
+end
+
+Complex.task